Analyses of the missions performed by and of the weapons aboard aircraft, in particular helicopters, have shown the need for both of the following:
an omnidirectional observation and detection function for target searching and for controlling the mission; and
a firing function that must firstly be rapid over a wide angular field both for target designation and for reflex firing of weapons for self-protection, and that must secondly be accurate over a narrow field of a few tens of degrees centered on the longitudinal axis of the aircraft for use with long-range weapons.
Patent EP-0 167 432 discloses an airborne system for detecting, locating, and tracking a target, the system comprising a pivotable optical head placed beneath a dome outside the fuselage of the aircraft. The optical detection and telemetry means are installed in a gimbal type mounting comprising two frames that are mutually perpendicular.
In addition, the optical sighting system for aircraft described in patent EP-0 127 914 is mounted in a pod including a first portion that is fixed to the aircraft, a second portion that is pivotable relative to said first portion about a first axis, and a third portion pivotable relative to said second portion about an axis orthogonal to the first-mentioned axis.
Also, patent FR-2 570 195 relates to apparatus for target searching, comprising a camera mounted on a tilting stabilization platform mounted on board an aircraft. In particular, the movement of the stabilization platform may be movement that is triangular, sinusoidal, sawtooth, or spiral.
In each of those cases, it thus appears that the sighting system is mounted outside the aircraft on a stabilized platform or the like whose description and hardware architecture show up difficulties of integration because such electromechanical equipment is heavy, bulky, and complex, and difficult to adapt to different carriers and weapons.